I have a really weird problem I've never encountered before. A freshly manufactured board I can program, ONCE. If I try to reprogram it, I get verification errors. If I try to erase the chip, the erase operation is successful but if I try to verify that it's blank I get an error - chip NOT blank.

I'm wondering if it doesn't have something to do with the board and what this processor does on it. It's a simple power supply/distribution board. More complex boards stack on it. It takes 28V in, and has three power supplies to create 12.0, 5.0, and 3.3V (each 2A). The processor simply monitors the voltage on each supply and controls 4 LEDs - one for each supply.

The PIC is powered from the 3.3V supply. A precision 2.048V reference is fed to AN0. A resistor divider from the 5, 12, and 28V supplies each feed the AN1-3 inputs. Based on the fact that the AN0 input is fixed, the voltage of the 3.3V supply can be calculated, and the rest of the supplies can then be easily measured.

Only thing I can think of is that the analog voltages are putting the chip into a weird latch-up condition or something like that. There's definitely some sort of interference/whatever which is preventing a full erase.

Last edited by newguy on Tue Nov 05, 2013 12:19 pm; edited 1 time in total

alan

Joined: 12 Nov 2012Posts: 285Location: South Africa

Posted: Wed Oct 23, 2013 3:03 pm

Hi newguy

It seems that somehow the U64 can only program some chips once> I had the same problem see (http://www.ccsinfo.com/forum/viewtopic.php?t=49444), but the ICD3 works without problems. In the meantime I have used my U64 for other chips so definitely not blown. Must admit I never contacted CCS, maybe now are a good time as it is not only me.

Regards

newguy

Joined: 24 Jun 2004Posts: 1555Location: Edmonton, Alberta

Posted: Thu Oct 24, 2013 8:39 am

Glad I'm not the only one. I did send an email to CCS support regarding the issue. 2nd one this week, as I learned Monday that the latest FW release for the Load-n-Go bricks dsPIC33FJ256GP710A's.

newguy

Joined: 24 Jun 2004Posts: 1555Location: Edmonton, Alberta

Posted: Tue Nov 05, 2013 12:19 pm

UPDATE: version 3.01 of ICD-U64 firmware fixes this issue.

gpsmikey

Joined: 16 Nov 2010Posts: 588Location: Kirkland, WA

Posted: Tue Nov 05, 2013 12:28 pm

"fixes this issue" - both problems or just one of them ? (there were two issues - one was bricking a chip the other was only able to program a different chip once)

mikey_________________mikey
-- you can't have too many gadgets or too much disk space !
old engineering saying: 1+1 = 3 for sufficiently large values of 1 or small values of 3

newguy

Joined: 24 Jun 2004Posts: 1555Location: Edmonton, Alberta

Posted: Tue Nov 05, 2013 12:58 pm

Just this issue. Two different programmers, one issue each. The Load-n-Go dsPIC33FJ issue is still outstanding.

gpsmikey

Joined: 16 Nov 2010Posts: 588Location: Kirkland, WA

Posted: Tue Nov 05, 2013 1:05 pm

Ah, ok, thanks for the clarification.

mikey_________________mikey
-- you can't have too many gadgets or too much disk space !
old engineering saying: 1+1 = 3 for sufficiently large values of 1 or small values of 3